Hey there Trailboss

You will be pleased to know that you are not going mad and that you are doing everything right in relation to aligning the IRS.

The thing is you are not alone in your problem and I believe it is safe to say that everyone with the 4.3 patch has this same issue.  From what I have read on the forums nobody can get the IRS GPS positions to change.  I think it must just be a problem with the 4.3 patch.

Hopefully it can be sorted in future updates.  Its not too big an issue anyway as its one of the more minor flight instruments.

Hope this helps

Regards
Neil